ToolTip : Java Glossary

Aka hoverhelp, value tip,
flyover help, or flyover label.
Explanatory text that pops up when you let your mouse linger over an icon or
component without clicking it. The text goes away automatically when you move your
mouse. You don’t have to dismiss it with a click the way you would with a
dialog box. Java makes it very easy to add tooltips to your
GUI (Graphic User Interface) application because every Swing component supports
JComponent. setToolTipText.